This benchtop unit represents a complete test set-up for the investigation of the mechanical efficiency of gears. The unit consists of the electronically regulated drive unit, which is included, and a magnetic brake. The constant braking effect can be very finely adjusted, it can thus be used as a definable load. A two stage spur gear unit and a worm gear unit form the basis of the experiments. Both gearboxes are commercially available industrial components. Their characteristics are matched to the performance of the drive unit. The components are installed on a sturdy frame made of aluminium section, this facilitates rapid and easy changes to the set-up.